问题 选择题

—Do you know_______?

—They moved here soon after their son was born. [ ]

A. when would the Greens move here

B. when the Greens moved here

C. the Greens would move here

D. when the Greens would move here

答案

B

多项选择题

图7-5所示的流程图描述了对8位二进制整数求补的算法。该算法的计算过程如下:从二进制数的低位(最右位)开始,依次向高位逐位查看,直到首次遇到“1”时,停止查看。然后,对该“1”位左面的更高位(如果有的话),逐位求反,所得的结果就是对原二进制数求补的结果。
例如:对二进制整数10101000求补的结果是01011000。
设8位二进制整数中的各位,从低位到高位,依次存放在整型数组BIT的BIT[1]~BIT[8]
中。例如,二进制整数10101000存放在数组BIT后,就有BIT[1]=0, BIT[2]=0, …, BIT[7]=0, BIT[8]=1。若流程图中存在空操作,则用NOP表示。
流程图中 (1) 处按“循环变量名:循环初值,增量,循环终值”格式描述。
[解析] 本题考查求补运算。求补运算是对一个数的各二进制位按位求反后再加1。例如:二进制10101000按位求反后得到的二进制是01010111,加1后为01011000。也可以这样来看,原二进制从最右边开始到遇到的第1个1为止都不变,而后面剩下的位按位求反即可。


本题流程图采用的是后一种思路,首先设置一个标志sw的值为0,从最右边一位开始往左循环遍历整个二进制数,到遇到第1个1后将标志位置1。由此可见,循环要进行8次,循环变量值依次从1递增到8。根据题目要求按“循环变量名:循环初值,增量,循环终值”格式描述循环,而循环开始下面一条判断是“BIT[i]=1”,所以循环变量是i,第1空应填i:1,1,8。
如果当前遍历的二进制位BIT[i]是1,且标志sw为0时,则证明是第1次遇到1,所以直接设置sw为1即可,故第2空应填1→sw。
如果当前遍历的二进制位BIT[i]是1,且标志sw为1时,说明已经不是第1次遇到1了,所以直接设置当前二进制位为0即可,故第3空应填0→BIT[i]。
如果当前遍历的二进制位BIT[i]是0,且标志sw为0时,则证明还没有遇到过一次1,所以该步什么都不用做,故第4空应填NOP。
如果当前遍历的二进制位BIT[i]是0,且标志sw为1时,说明已经遇到过1了,所以该步需将当前的二进制位求反,故第5空应填1→BIT[i]。

阅读理解

阅读理解。

     One of the greatest contributions to the first Oxford English Dictionary was also one of its most

unusual. In 1879, Oxford University in England asked Prof. James Murray to serve as editor for what

was to be the most ambitious dictionary in the history of the English language. It would include every

English word possible and would give not only the definition but also the history of the word and

quotations (引文) showing how it was used.

     This was a huge task.,so Murrary had to find volunteers from Britain, the United States, and the

British colonies to search every newspaper, magazine, and book ever written in English. Hundreds of

volunteers responded, including William Chester Minor. Dr. Minor was an American surgeon who had

served in the Civil War and was now living in England. He gave his address as "Broadmoor, Crowthorne, Berkshire,"" 50 miles from Oxford.

     Minor joined the army of volunteers sending words and quotations to Murray. Over the next 17 years, he became one of the staff's most valued contributors.

     But he was also a mystery. In spite of many invitations, he would always decline to visit Oxford. So in

1897, Murray finally decided to travel to Crowthorne himself. When he arrived, he found Minor locked

in a book-lined cell at the Broadmoor Asylum (精神病院) for the Criminally insane.

     Murray and Minor became friends, sharing their love of words. Minor continued contributing to the

dictionary, sending in more than 10,000 submissions in 20 years. Murray continued to visit Minor

regularly, sometimes taking walks with him around the asylum grounds.

     In 1910, Minor left Broadmoor for an asylum in his native America. Murray was at the port to wave

goodbye to his remarkable friend.

     Minor died in 1920, seven years before the first edition of the Oxford English Dictionary was

completed. The 12 volumes defined 414,825 words, and thousands of them were contributions from a

very scholarly and devoted asylum patient.

1. According to the text, the first Oxford English Dictionary _________.

A. came out before minor died

B. was edited by an American volunteer

C. included the English words invented by Murray

D. was intended to be the most ambitious English dictionary

2. How did Dr. Minor contributed to the dictionary?

A. He helped Murray to find hundreds of volunteers.

B. He sent newspapers, magazines and books to Murray.

C. He provided a great number of words and quotations

D. he went to England to work with Murray.

3. Why did Dr. Minor refuse to visit Oxford?

A. He was shut in an asylum

B. He lived far from Oxford

C. He was busy writing a book      

D. He disliked traveling

4. Prof. Murray and Dr. Minor became friends mainly because __________.

A. they both served in the Civil War.

B. They had a common interest in words

C. Minor recovered with the help of Murray

D. Murray went to America regularly to visit Minor

5. Which of the following best describe Dr. Minor?

A. Brave and determined

B. Cautious and friendly

C. Considerate and optimistic

D. Unusual and scholarly

6. What does the text mainly talk about?

A. The history of the English language.

B. The friendship between Murray and Minor

C. Minor and the first Oxford English Dictionary

D. Broadmoor Asylum and is patients